Unit 2 Algebra 8 Exam-style question There are 300 ml (millilitres) of medicine in a bottle. Mary has to take two 5 ml spoons full of medicine twice a day. Mary has to take the medicine until the bottle is empty. Take two 5 ml spoons full twice a day a How many days does Mary have to take the medicine for? (3 marks) You can work out the amount of medicine, c ml, to give to a child using the formula ma c = ___ 150 m is the age of the child, in months a is an adult dose, in ml. Exam hint You must show how you worked out your answer so that the examiner can see your method. A child is 30 months old. An adult’s dose is 40 ml. b Work out the amount of medicine you can give to the child. (2 marks) Exam hint ma means m × a June 2012, Q26, 1MA0/1F 9 Expand a 9(x + 2y − z) b −2(r − 7t − 3s) c 3c(3a − 3b) d −p(r − s − t) e 5x(x + 8y − 9z) 10 Factorise a −7t − 21 b −a2 − 5a 11 c −6f 2 − 12f d −2r − 4r2 Exam-style question a Expand 5(2c + 3d) b Here are two straight lines, ABCDE and PQ. x13 x A B (1 mark) Diagrams NOT accurately drawn 2x C D Exam hint First work out the length of AE in terms of x. E 3x 2 2 P Q In the diagrams all the lengths are in cm. AE = 2PQ Find an expression, in terms of x, for the length of DE. Give your answer in its simplest form. (4 marks) Nov 2013, Q15, 5MB2F/01 12 Reasoning Alex says that when you raise a negative number to an even power the answer is always positive, and when you raise a negative number to an odd power the answer is always negative. Is he right? Give reasons for your answer. 54